Receive the latest local updates in your inbox

One political expert and pollster analyzes the inaugural speech given by New Jersey Governor Chris Christie, as he starts his second term in the shadow of the Bridgegate scandal. (Published Wednesday, Jan. 22, 2014)

Updated at 5:15 AM EDT on Thursday, Jan 23, 2014

The FBI is now questioning witnesses in their investigation of threats over Sandy relief funds allegedly made by aides for NJ Governor Chris Christie, according to NBC News sources.

On Sunday, Hoboken Mayor Dawn Zimmer claimed senior members of Christie's administration, including Lt. Gov. Kim Guadagno, warned her last year that if she didn't approve a development project the governor supported, then the state would withhold grants that would help her city rebound form Hurricane Sandy. Guadagno and a Christie spokesman denied the charge.

Sources close to the investigation told NBC News on Wednesday that FBI agents are now investigating the accusations and have instructed witnesses to “preserve all documents and emails relating to the allegations.”

Zimmer claimed that Guadagno pulled her aside at a supermarket opening in May and said Hoboken's storm recovery funds hinged on Zimmer's approval of a commercial development whose lawyer and lobbyist are close to the governor. On Sunday, Zimmer told CNN the ultimatum was delivered on behalf of the governor, a possible 2016 presidential candidate.

Guadagno called Zimmer’s allegations "false" and "illogical.” Marc Ferzan, executive director of the Governor's Office of Recovery and Rebuilding, told reporters in a conference call that Hoboken has been treated no differently than other cities with respect to storm relief funds.

Zimmer met with investigators from the U.S. attorney's office for several hours on Sunday and gave them journal entries she said were made at the time of the conversation. She also has offered to take a lie-detector test or testify under oath.

Ferzan, during his conference call, said claims that Hoboken received less than its fair share of disaster aid were a "mischaracterization."

Superstorm Sandy, which was spawned in October 2012 when Hurricane Sandy merged with two other weather systems, killed people in 10 states, but New Jersey and New York were hit the hardest. It's New Jersey's worst natural disaster.

Ferzan said the state has received more than $14 billion in requests statewide for Hazard Mitigation grants but has only about $300 million to disburse. Christie administration officials have said Hoboken has requested more than $100 million in such funding.

He said the state has tried to prioritize its funding and programs to address the "communities most in need" and purposely directed most of the recovery funding toward homeowners, business owners and renters.

Federal authorities and state legislators are investigating another scandal involving the Christie administration — allegations that the governor's top aides orchestrated traffic jams in Fort Lee by blocking off lanes to the George Washington Bridge, which connects to New York City, possibly to punish the town's Democratic mayor for not endorsing the governor for re-election.